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1/*
2 * Copyright (C) 1992, 1998-2006 Linus Torvalds, Ingo Molnar
3 * Copyright (C) 2005-2006, Thomas Gleixner, Russell King
4 *
5 * This file contains the interrupt descriptor management code
6 *
7 * Detailed information is available in Documentation/DocBook/genericirq
8 *
9 */
10#include <linux/irq.h>
11#include <linux/slab.h>
12#include <linux/export.h>
13#include <linux/interrupt.h>
14#include <linux/kernel_stat.h>
15#include <linux/radix-tree.h>
16#include <linux/bitmap.h>
17#include <linux/irqdomain.h>
18#include <linux/sysfs.h>
19
20#include "internals.h"
21
22/*
23 * lockdep: we want to handle all irq_desc locks as a single lock-class:
24 */
25static struct lock_class_key irq_desc_lock_class;
26
27#if defined(CONFIG_SMP)
28static int __init irq_affinity_setup(char *str)
29{
30 zalloc_cpumask_var(&irq_default_affinity, GFP_NOWAIT);
31 cpulist_parse(str, irq_default_affinity);
32 /*
33 * Set at least the boot cpu. We don't want to end up with
34 * bugreports caused by random comandline masks
35 */
36 cpumask_set_cpu(smp_processor_id(), irq_default_affinity);
37 return 1;
38}
39__setup("irqaffinity=", irq_affinity_setup);
40
41static void __init init_irq_default_affinity(void)
42{
43#ifdef CONFIG_CPUMASK_OFFSTACK
44 if (!irq_default_affinity)
45 zalloc_cpumask_var(&irq_default_affinity, GFP_NOWAIT);
46#endif
47 if (cpumask_empty(irq_default_affinity))
48 cpumask_setall(irq_default_affinity);
49}
50#else
51static void __init init_irq_default_affinity(void)
52{
53}
54#endif
55
56#ifdef CONFIG_SMP
57static int alloc_masks(struct irq_desc *desc, gfp_t gfp, int node)
58{
59 if (!zalloc_cpumask_var_node(&desc->irq_common_data.affinity,
60 gfp, node))
61 return -ENOMEM;
62
63#ifdef CONFIG_GENERIC_PENDING_IRQ
64 if (!zalloc_cpumask_var_node(&desc->pending_mask, gfp, node)) {
65 free_cpumask_var(desc->irq_common_data.affinity);
66 return -ENOMEM;
67 }
68#endif
69 return 0;
70}
71
72static void desc_smp_init(struct irq_desc *desc, int node,
73 const struct cpumask *affinity)
74{
75 if (!affinity)
76 affinity = irq_default_affinity;
77 cpumask_copy(desc->irq_common_data.affinity, affinity);
78
79#ifdef CONFIG_GENERIC_PENDING_IRQ
80 cpumask_clear(desc->pending_mask);
81#endif
82#ifdef CONFIG_NUMA
83 desc->irq_common_data.node = node;
84#endif
85}
86
87#else
88static inline int
89alloc_masks(struct irq_desc *desc, gfp_t gfp, int node) { return 0; }
90static inline void
91desc_smp_init(struct irq_desc *desc, int node, const struct cpumask *affinity) { }
92#endif
93
94static void desc_set_defaults(unsigned int irq, struct irq_desc *desc, int node,
95 const struct cpumask *affinity, struct module *owner)
96{
97 int cpu;
98
99 desc->irq_common_data.handler_data = NULL;
100 desc->irq_common_data.msi_desc = NULL;
101
102 desc->irq_data.common = &desc->irq_common_data;
103 desc->irq_data.irq = irq;
104 desc->irq_data.chip = &no_irq_chip;
105 desc->irq_data.chip_data = NULL;
106 irq_settings_clr_and_set(desc, ~0, _IRQ_DEFAULT_INIT_FLAGS);
107 irqd_set(&desc->irq_data, IRQD_IRQ_DISABLED);
108 desc->handle_irq = handle_bad_irq;
109 desc->depth = 1;
110 desc->irq_count = 0;
111 desc->irqs_unhandled = 0;
112 desc->name = NULL;
113 desc->owner = owner;
114 for_each_possible_cpu(cpu)
115 *per_cpu_ptr(desc->kstat_irqs, cpu) = 0;
116 desc_smp_init(desc, node, affinity);
117}
118
119int nr_irqs = NR_IRQS;
120EXPORT_SYMBOL_GPL(nr_irqs);
121
122static DEFINE_MUTEX(sparse_irq_lock);
123static DECLARE_BITMAP(allocated_irqs, IRQ_BITMAP_BITS);
124
125#ifdef CONFIG_SPARSE_IRQ
126
127static void irq_kobj_release(struct kobject *kobj);
128
129#ifdef CONFIG_SYSFS
130static struct kobject *irq_kobj_base;
131
132#define IRQ_ATTR_RO(_name) \
133static struct kobj_attribute _name##_attr = __ATTR_RO(_name)
134
135static ssize_t per_cpu_count_show(struct kobject *kobj,
136 struct kobj_attribute *attr, char *buf)
137{
138 struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
139 int cpu, irq = desc->irq_data.irq;
140 ssize_t ret = 0;
141 char *p = "";
142
143 for_each_possible_cpu(cpu) {
144 unsigned int c = kstat_irqs_cpu(irq, cpu);
145
146 ret += scnprintf(buf + ret, PAGE_SIZE - ret, "%s%u", p, c);
147 p = ",";
148 }
149
150 ret += scnprintf(buf + ret, PAGE_SIZE - ret, "\n");
151 return ret;
152}
153IRQ_ATTR_RO(per_cpu_count);
154
155static ssize_t chip_name_show(struct kobject *kobj,
156 struct kobj_attribute *attr, char *buf)
157{
158 struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
159 ssize_t ret = 0;
160
161 raw_spin_lock_irq(&desc->lock);
162 if (desc->irq_data.chip && desc->irq_data.chip->name) {
163 ret = scnprintf(buf, PAGE_SIZE, "%s\n",
164 desc->irq_data.chip->name);
165 }
166 raw_spin_unlock_irq(&desc->lock);
167
168 return ret;
169}
170IRQ_ATTR_RO(chip_name);
171
172static ssize_t hwirq_show(struct kobject *kobj,
173 struct kobj_attribute *attr, char *buf)
174{
175 struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
176 ssize_t ret = 0;
177
178 raw_spin_lock_irq(&desc->lock);
179 if (desc->irq_data.domain)
180 ret = sprintf(buf, "%d\n", (int)desc->irq_data.hwirq);
181 raw_spin_unlock_irq(&desc->lock);
182
183 return ret;
184}
185IRQ_ATTR_RO(hwirq);
186
187static ssize_t type_show(struct kobject *kobj,
188 struct kobj_attribute *attr, char *buf)
189{
190 struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
191 ssize_t ret = 0;
192
193 raw_spin_lock_irq(&desc->lock);
194 ret = sprintf(buf, "%s\n",
195 irqd_is_level_type(&desc->irq_data) ? "level" : "edge");
196 raw_spin_unlock_irq(&desc->lock);
197
198 return ret;
199
200}
201IRQ_ATTR_RO(type);
202
203static ssize_t name_show(struct kobject *kobj,
204 struct kobj_attribute *attr, char *buf)
205{
206 struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
207 ssize_t ret = 0;
208
209 raw_spin_lock_irq(&desc->lock);
210 if (desc->name)
211 ret = scnprintf(buf, PAGE_SIZE, "%s\n", desc->name);
212 raw_spin_unlock_irq(&desc->lock);
213
214 return ret;
215}
216IRQ_ATTR_RO(name);
217
218static ssize_t actions_show(struct kobject *kobj,
219 struct kobj_attribute *attr, char *buf)
220{
221 struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
222 struct irqaction *action;
223 ssize_t ret = 0;
224 char *p = "";
225
226 raw_spin_lock_irq(&desc->lock);
227 for (action = desc->action; action != NULL; action = action->next) {
228 ret += scnprintf(buf + ret, PAGE_SIZE - ret, "%s%s",
229 p, action->name);
230 p = ",";
231 }
232 raw_spin_unlock_irq(&desc->lock);
233
234 if (ret)
235 ret += scnprintf(buf + ret, PAGE_SIZE - ret, "\n");
236
237 return ret;
238}
239IRQ_ATTR_RO(actions);
240
241static struct attribute *irq_attrs[] = {
242 &per_cpu_count_attr.attr,
243 &chip_name_attr.attr,
244 &hwirq_attr.attr,
245 &type_attr.attr,
246 &name_attr.attr,
247 &actions_attr.attr,
248 NULL
249};
250
251static struct kobj_type irq_kobj_type = {
252 .release = irq_kobj_release,
253 .sysfs_ops = &kobj_sysfs_ops,
254 .default_attrs = irq_attrs,
255};
256
257static void irq_sysfs_add(int irq, struct irq_desc *desc)
258{
259 if (irq_kobj_base) {
260 /*
261 * Continue even in case of failure as this is nothing
262 * crucial.
263 */
264 if (kobject_add(&desc->kobj, irq_kobj_base, "%d", irq))
265 pr_warn("Failed to add kobject for irq %d\n", irq);
266 }
267}
268
269static int __init irq_sysfs_init(void)
270{
271 struct irq_desc *desc;
272 int irq;
273
274 /* Prevent concurrent irq alloc/free */
275 irq_lock_sparse();
276
277 irq_kobj_base = kobject_create_and_add("irq", kernel_kobj);
278 if (!irq_kobj_base) {
279 irq_unlock_sparse();
280 return -ENOMEM;
281 }
282
283 /* Add the already allocated interrupts */
284 for_each_irq_desc(irq, desc)
285 irq_sysfs_add(irq, desc);
286 irq_unlock_sparse();
287
288 return 0;
289}
290postcore_initcall(irq_sysfs_init);
291
292#else /* !CONFIG_SYSFS */
293
294static struct kobj_type irq_kobj_type = {
295 .release = irq_kobj_release,
296};
297
298static void irq_sysfs_add(int irq, struct irq_desc *desc) {}
299
300#endif /* CONFIG_SYSFS */
301
302static RADIX_TREE(irq_desc_tree, GFP_KERNEL);
303
304static void irq_insert_desc(unsigned int irq, struct irq_desc *desc)
305{
306 radix_tree_insert(&irq_desc_tree, irq, desc);
307}
308
309struct irq_desc *irq_to_desc(unsigned int irq)
310{
311 return radix_tree_lookup(&irq_desc_tree, irq);
312}
313EXPORT_SYMBOL(irq_to_desc);
314
315static void delete_irq_desc(unsigned int irq)
316{
317 radix_tree_delete(&irq_desc_tree, irq);
318}
319
320#ifdef CONFIG_SMP
321static void free_masks(struct irq_desc *desc)
322{
323#ifdef CONFIG_GENERIC_PENDING_IRQ
324 free_cpumask_var(desc->pending_mask);
325#endif
326 free_cpumask_var(desc->irq_common_data.affinity);
327}
328#else
329static inline void free_masks(struct irq_desc *desc) { }
330#endif
331
332void irq_lock_sparse(void)
333{
334 mutex_lock(&sparse_irq_lock);
335}
336
337void irq_unlock_sparse(void)
338{
339 mutex_unlock(&sparse_irq_lock);
340}
341
342static struct irq_desc *alloc_desc(int irq, int node, unsigned int flags,
343 const struct cpumask *affinity,
344 struct module *owner)
345{
346 struct irq_desc *desc;
347 gfp_t gfp = GFP_KERNEL;
348
349 desc = kzalloc_node(sizeof(*desc), gfp, node);
350 if (!desc)
351 return NULL;
352 /* allocate based on nr_cpu_ids */
353 desc->kstat_irqs = alloc_percpu(unsigned int);
354 if (!desc->kstat_irqs)
355 goto err_desc;
356
357 if (alloc_masks(desc, gfp, node))
358 goto err_kstat;
359
360 raw_spin_lock_init(&desc->lock);
361 lockdep_set_class(&desc->lock, &irq_desc_lock_class);
362 init_rcu_head(&desc->rcu);
363
364 desc_set_defaults(irq, desc, node, affinity, owner);
365 irqd_set(&desc->irq_data, flags);
366 kobject_init(&desc->kobj, &irq_kobj_type);
367
368 return desc;
369
370err_kstat:
371 free_percpu(desc->kstat_irqs);
372err_desc:
373 kfree(desc);
374 return NULL;
375}
376
377static void irq_kobj_release(struct kobject *kobj)
378{
379 struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
380
381 free_masks(desc);
382 free_percpu(desc->kstat_irqs);
383 kfree(desc);
384}
385
386static void delayed_free_desc(struct rcu_head *rhp)
387{
388 struct irq_desc *desc = container_of(rhp, struct irq_desc, rcu);
389
390 kobject_put(&desc->kobj);
391}
392
393static void free_desc(unsigned int irq)
394{
395 struct irq_desc *desc = irq_to_desc(irq);
396
397 unregister_irq_proc(irq, desc);
398
399 /*
400 * sparse_irq_lock protects also show_interrupts() and
401 * kstat_irq_usr(). Once we deleted the descriptor from the
402 * sparse tree we can free it. Access in proc will fail to
403 * lookup the descriptor.
404 *
405 * The sysfs entry must be serialized against a concurrent
406 * irq_sysfs_init() as well.
407 */
408 mutex_lock(&sparse_irq_lock);
409 kobject_del(&desc->kobj);
410 delete_irq_desc(irq);
411 mutex_unlock(&sparse_irq_lock);
412
413 /*
414 * We free the descriptor, masks and stat fields via RCU. That
415 * allows demultiplex interrupts to do rcu based management of
416 * the child interrupts.
417 */
418 call_rcu(&desc->rcu, delayed_free_desc);
419}
420
421static int alloc_descs(unsigned int start, unsigned int cnt, int node,
422 const struct cpumask *affinity, struct module *owner)
423{
424 const struct cpumask *mask = NULL;
425 struct irq_desc *desc;
426 unsigned int flags;
427 int i;
428
429 /* Validate affinity mask(s) */
430 if (affinity) {
431 for (i = 0, mask = affinity; i < cnt; i++, mask++) {
432 if (cpumask_empty(mask))
433 return -EINVAL;
434 }
435 }
436
437 flags = affinity ? IRQD_AFFINITY_MANAGED : 0;
438 mask = NULL;
439
440 for (i = 0; i < cnt; i++) {
441 if (affinity) {
442 node = cpu_to_node(cpumask_first(affinity));
443 mask = affinity;
444 affinity++;
445 }
446 desc = alloc_desc(start + i, node, flags, mask, owner);
447 if (!desc)
448 goto err;
449 mutex_lock(&sparse_irq_lock);
450 irq_insert_desc(start + i, desc);
451 irq_sysfs_add(start + i, desc);
452 mutex_unlock(&sparse_irq_lock);
453 }
454 return start;
455
456err:
457 for (i--; i >= 0; i--)
458 free_desc(start + i);
459
460 mutex_lock(&sparse_irq_lock);
461 bitmap_clear(allocated_irqs, start, cnt);
462 mutex_unlock(&sparse_irq_lock);
463 return -ENOMEM;
464}
465
466static int irq_expand_nr_irqs(unsigned int nr)
467{
468 if (nr > IRQ_BITMAP_BITS)
469 return -ENOMEM;
470 nr_irqs = nr;
471 return 0;
472}
473
474int __init early_irq_init(void)
475{
476 int i, initcnt, node = first_online_node;
477 struct irq_desc *desc;
478
479 init_irq_default_affinity();
480
481 /* Let arch update nr_irqs and return the nr of preallocated irqs */
482 initcnt = arch_probe_nr_irqs();
483 printk(KERN_INFO "NR_IRQS:%d nr_irqs:%d %d\n", NR_IRQS, nr_irqs, initcnt);
484
485 if (WARN_ON(nr_irqs > IRQ_BITMAP_BITS))
486 nr_irqs = IRQ_BITMAP_BITS;
487
488 if (WARN_ON(initcnt > IRQ_BITMAP_BITS))
489 initcnt = IRQ_BITMAP_BITS;
490
491 if (initcnt > nr_irqs)
492 nr_irqs = initcnt;
493
494 for (i = 0; i < initcnt; i++) {
495 desc = alloc_desc(i, node, 0, NULL, NULL);
496 set_bit(i, allocated_irqs);
497 irq_insert_desc(i, desc);
498 }
499 return arch_early_irq_init();
500}
501
502#else /* !CONFIG_SPARSE_IRQ */
503
504struct irq_desc irq_desc[NR_IRQS] __cacheline_aligned_in_smp = {
505 [0 ... NR_IRQS-1] = {
506 .handle_irq = handle_bad_irq,
507 .depth = 1,
508 .lock = __RAW_SPIN_LOCK_UNLOCKED(irq_desc->lock),
509 }
510};
511
512int __init early_irq_init(void)
513{
514 int count, i, node = first_online_node;
515 struct irq_desc *desc;
516
517 init_irq_default_affinity();
518
519 printk(KERN_INFO "NR_IRQS:%d\n", NR_IRQS);
520
521 desc = irq_desc;
522 count = ARRAY_SIZE(irq_desc);
523
524 for (i = 0; i < count; i++) {
525 desc[i].kstat_irqs = alloc_percpu(unsigned int);
526 alloc_masks(&desc[i], GFP_KERNEL, node);
527 raw_spin_lock_init(&desc[i].lock);
528 lockdep_set_class(&desc[i].lock, &irq_desc_lock_class);
529 desc_set_defaults(i, &desc[i], node, NULL, NULL);
530 }
531 return arch_early_irq_init();
532}
533
534struct irq_desc *irq_to_desc(unsigned int irq)
535{
536 return (irq < NR_IRQS) ? irq_desc + irq : NULL;
537}
538EXPORT_SYMBOL(irq_to_desc);
539
540static void free_desc(unsigned int irq)
541{
542 struct irq_desc *desc = irq_to_desc(irq);
543 unsigned long flags;
544
545 raw_spin_lock_irqsave(&desc->lock, flags);
546 desc_set_defaults(irq, desc, irq_desc_get_node(desc), NULL, NULL);
547 raw_spin_unlock_irqrestore(&desc->lock, flags);
548}
549
550static inline int alloc_descs(unsigned int start, unsigned int cnt, int node,
551 const struct cpumask *affinity,
552 struct module *owner)
553{
554 u32 i;
555
556 for (i = 0; i < cnt; i++) {
557 struct irq_desc *desc = irq_to_desc(start + i);
558
559 desc->owner = owner;
560 }
561 return start;
562}
563
564static int irq_expand_nr_irqs(unsigned int nr)
565{
566 return -ENOMEM;
567}
568
569void irq_mark_irq(unsigned int irq)
570{
571 mutex_lock(&sparse_irq_lock);
572 bitmap_set(allocated_irqs, irq, 1);
573 mutex_unlock(&sparse_irq_lock);
574}
575
576#ifdef CONFIG_GENERIC_IRQ_LEGACY
577void irq_init_desc(unsigned int irq)
578{
579 free_desc(irq);
580}
581#endif
582
583#endif /* !CONFIG_SPARSE_IRQ */
584
585/**
586 * generic_handle_irq - Invoke the handler for a particular irq
587 * @irq: The irq number to handle
588 *
589 */
590int generic_handle_irq(unsigned int irq)
591{
592 struct irq_desc *desc = irq_to_desc(irq);
593
594 if (!desc)
595 return -EINVAL;
596 generic_handle_irq_desc(desc);
597 return 0;
598}
599EXPORT_SYMBOL_GPL(generic_handle_irq);
600
601#ifdef CONFIG_HANDLE_DOMAIN_IRQ
602/**
603 * __handle_domain_irq - Invoke the handler for a HW irq belonging to a domain
604 * @domain: The domain where to perform the lookup
605 * @hwirq: The HW irq number to convert to a logical one
606 * @lookup: Whether to perform the domain lookup or not
607 * @regs: Register file coming from the low-level handling code
608 *
609 * Returns: 0 on success, or -EINVAL if conversion has failed
610 */
611int __handle_domain_irq(struct irq_domain *domain, unsigned int hwirq,
612 bool lookup, struct pt_regs *regs)
613{
614 struct pt_regs *old_regs = set_irq_regs(regs);
615 unsigned int irq = hwirq;
616 int ret = 0;
617
618 irq_enter();
619
620#ifdef CONFIG_IRQ_DOMAIN
621 if (lookup)
622 irq = irq_find_mapping(domain, hwirq);
623#endif
624
625 /*
626 * Some hardware gives randomly wrong interrupts. Rather
627 * than crashing, do something sensible.
628 */
629 if (unlikely(!irq || irq >= nr_irqs)) {
630 ack_bad_irq(irq);
631 ret = -EINVAL;
632 } else {
633 generic_handle_irq(irq);
634 }
635
636 irq_exit();
637 set_irq_regs(old_regs);
638 return ret;
639}
640#endif
641
642/* Dynamic interrupt handling */
643
644/**
645 * irq_free_descs - free irq descriptors
646 * @from: Start of descriptor range
647 * @cnt: Number of consecutive irqs to free
648 */
649void irq_free_descs(unsigned int from, unsigned int cnt)
650{
651 int i;
652
653 if (from >= nr_irqs || (from + cnt) > nr_irqs)
654 return;
655
656 for (i = 0; i < cnt; i++)
657 free_desc(from + i);
658
659 mutex_lock(&sparse_irq_lock);
660 bitmap_clear(allocated_irqs, from, cnt);
661 mutex_unlock(&sparse_irq_lock);
662}
663EXPORT_SYMBOL_GPL(irq_free_descs);
664
665/**
666 * irq_alloc_descs - allocate and initialize a range of irq descriptors
667 * @irq: Allocate for specific irq number if irq >= 0
668 * @from: Start the search from this irq number
669 * @cnt: Number of consecutive irqs to allocate.
670 * @node: Preferred node on which the irq descriptor should be allocated
671 * @owner: Owning module (can be NULL)
672 * @affinity: Optional pointer to an affinity mask array of size @cnt which
673 * hints where the irq descriptors should be allocated and which
674 * default affinities to use
675 *
676 * Returns the first irq number or error code
677 */
678int __ref
679__irq_alloc_descs(int irq, unsigned int from, unsigned int cnt, int node,
680 struct module *owner, const struct cpumask *affinity)
681{
682 int start, ret;
683
684 if (!cnt)
685 return -EINVAL;
686
687 if (irq >= 0) {
688 if (from > irq)
689 return -EINVAL;
690 from = irq;
691 } else {
692 /*
693 * For interrupts which are freely allocated the
694 * architecture can force a lower bound to the @from
695 * argument. x86 uses this to exclude the GSI space.
696 */
697 from = arch_dynirq_lower_bound(from);
698 }
699
700 mutex_lock(&sparse_irq_lock);
701
702 start = bitmap_find_next_zero_area(allocated_irqs, IRQ_BITMAP_BITS,
703 from, cnt, 0);
704 ret = -EEXIST;
705 if (irq >=0 && start != irq)
706 goto err;
707
708 if (start + cnt > nr_irqs) {
709 ret = irq_expand_nr_irqs(start + cnt);
710 if (ret)
711 goto err;
712 }
713
714 bitmap_set(allocated_irqs, start, cnt);
715 mutex_unlock(&sparse_irq_lock);
716 return alloc_descs(start, cnt, node, affinity, owner);
717
718err:
719 mutex_unlock(&sparse_irq_lock);
720 return ret;
721}
722EXPORT_SYMBOL_GPL(__irq_alloc_descs);
723
724#ifdef CONFIG_GENERIC_IRQ_LEGACY_ALLOC_HWIRQ
725/**
726 * irq_alloc_hwirqs - Allocate an irq descriptor and initialize the hardware
727 * @cnt: number of interrupts to allocate
728 * @node: node on which to allocate
729 *
730 * Returns an interrupt number > 0 or 0, if the allocation fails.
731 */
732unsigned int irq_alloc_hwirqs(int cnt, int node)
733{
734 int i, irq = __irq_alloc_descs(-1, 0, cnt, node, NULL, NULL);
735
736 if (irq < 0)
737 return 0;
738
739 for (i = irq; cnt > 0; i++, cnt--) {
740 if (arch_setup_hwirq(i, node))
741 goto err;
742 irq_clear_status_flags(i, _IRQ_NOREQUEST);
743 }
744 return irq;
745
746err:
747 for (i--; i >= irq; i--) {
748 irq_set_status_flags(i, _IRQ_NOREQUEST | _IRQ_NOPROBE);
749 arch_teardown_hwirq(i);
750 }
751 irq_free_descs(irq, cnt);
752 return 0;
753}
754EXPORT_SYMBOL_GPL(irq_alloc_hwirqs);
755
756/**
757 * irq_free_hwirqs - Free irq descriptor and cleanup the hardware
758 * @from: Free from irq number
759 * @cnt: number of interrupts to free
760 *
761 */
762void irq_free_hwirqs(unsigned int from, int cnt)
763{
764 int i, j;
765
766 for (i = from, j = cnt; j > 0; i++, j--) {
767 irq_set_status_flags(i, _IRQ_NOREQUEST | _IRQ_NOPROBE);
768 arch_teardown_hwirq(i);
769 }
770 irq_free_descs(from, cnt);
771}
772EXPORT_SYMBOL_GPL(irq_free_hwirqs);
773#endif
774
775/**
776 * irq_get_next_irq - get next allocated irq number
777 * @offset: where to start the search
778 *
779 * Returns next irq number after offset or nr_irqs if none is found.
780 */
781unsigned int irq_get_next_irq(unsigned int offset)
782{
783 return find_next_bit(allocated_irqs, nr_irqs, offset);
784}
785
786struct irq_desc *
787__irq_get_desc_lock(unsigned int irq, unsigned long *flags, bool bus,
788 unsigned int check)
789{
790 struct irq_desc *desc = irq_to_desc(irq);
791
792 if (desc) {
793 if (check & _IRQ_DESC_CHECK) {
794 if ((check & _IRQ_DESC_PERCPU) &&
795 !irq_settings_is_per_cpu_devid(desc))
796 return NULL;
797
798 if (!(check & _IRQ_DESC_PERCPU) &&
799 irq_settings_is_per_cpu_devid(desc))
800 return NULL;
801 }
802
803 if (bus)
804 chip_bus_lock(desc);
805 raw_spin_lock_irqsave(&desc->lock, *flags);
806 }
807 return desc;
808}
809
810void __irq_put_desc_unlock(struct irq_desc *desc, unsigned long flags, bool bus)
811{
812 raw_spin_unlock_irqrestore(&desc->lock, flags);
813 if (bus)
814 chip_bus_sync_unlock(desc);
815}
816
817int irq_set_percpu_devid_partition(unsigned int irq,
818 const struct cpumask *affinity)
819{
820 struct irq_desc *desc = irq_to_desc(irq);
821
822 if (!desc)
823 return -EINVAL;
824
825 if (desc->percpu_enabled)
826 return -EINVAL;
827
828 desc->percpu_enabled = kzalloc(sizeof(*desc->percpu_enabled), GFP_KERNEL);
829
830 if (!desc->percpu_enabled)
831 return -ENOMEM;
832
833 if (affinity)
834 desc->percpu_affinity = affinity;
835 else
836 desc->percpu_affinity = cpu_possible_mask;
837
838 irq_set_percpu_devid_flags(irq);
839 return 0;
840}
841
842int irq_set_percpu_devid(unsigned int irq)
843{
844 return irq_set_percpu_devid_partition(irq, NULL);
845}
846
847int irq_get_percpu_devid_partition(unsigned int irq, struct cpumask *affinity)
848{
849 struct irq_desc *desc = irq_to_desc(irq);
850
851 if (!desc || !desc->percpu_enabled)
852 return -EINVAL;
853
854 if (affinity)
855 cpumask_copy(affinity, desc->percpu_affinity);
856
857 return 0;
858}
859
860void kstat_incr_irq_this_cpu(unsigned int irq)
861{
862 kstat_incr_irqs_this_cpu(irq_to_desc(irq));
863}
864
865/**
866 * kstat_irqs_cpu - Get the statistics for an interrupt on a cpu
867 * @irq: The interrupt number
868 * @cpu: The cpu number
869 *
870 * Returns the sum of interrupt counts on @cpu since boot for
871 * @irq. The caller must ensure that the interrupt is not removed
872 * concurrently.
873 */
874unsigned int kstat_irqs_cpu(unsigned int irq, int cpu)
875{
876 struct irq_desc *desc = irq_to_desc(irq);
877
878 return desc && desc->kstat_irqs ?
879 *per_cpu_ptr(desc->kstat_irqs, cpu) : 0;
880}
881
882/**
883 * kstat_irqs - Get the statistics for an interrupt
884 * @irq: The interrupt number
885 *
886 * Returns the sum of interrupt counts on all cpus since boot for
887 * @irq. The caller must ensure that the interrupt is not removed
888 * concurrently.
889 */
890unsigned int kstat_irqs(unsigned int irq)
891{
892 struct irq_desc *desc = irq_to_desc(irq);
893 int cpu;
894 unsigned int sum = 0;
895
896 if (!desc || !desc->kstat_irqs)
897 return 0;
898 for_each_possible_cpu(cpu)
899 sum += *per_cpu_ptr(desc->kstat_irqs, cpu);
900 return sum;
901}
902
903/**
904 * kstat_irqs_usr - Get the statistics for an interrupt
905 * @irq: The interrupt number
906 *
907 * Returns the sum of interrupt counts on all cpus since boot for
908 * @irq. Contrary to kstat_irqs() this can be called from any
909 * preemptible context. It's protected against concurrent removal of
910 * an interrupt descriptor when sparse irqs are enabled.
911 */
912unsigned int kstat_irqs_usr(unsigned int irq)
913{
914 unsigned int sum;
915
916 irq_lock_sparse();
917 sum = kstat_irqs(irq);
918 irq_unlock_sparse();
919 return sum;
920}
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright (C) 1992, 1998-2006 Linus Torvalds, Ingo Molnar
4 * Copyright (C) 2005-2006, Thomas Gleixner, Russell King
5 *
6 * This file contains the interrupt descriptor management code. Detailed
7 * information is available in Documentation/core-api/genericirq.rst
8 *
9 */
10#include <linux/irq.h>
11#include <linux/slab.h>
12#include <linux/export.h>
13#include <linux/interrupt.h>
14#include <linux/kernel_stat.h>
15#include <linux/radix-tree.h>
16#include <linux/bitmap.h>
17#include <linux/irqdomain.h>
18#include <linux/sysfs.h>
19
20#include "internals.h"
21
22/*
23 * lockdep: we want to handle all irq_desc locks as a single lock-class:
24 */
25static struct lock_class_key irq_desc_lock_class;
26
27#if defined(CONFIG_SMP)
28static int __init irq_affinity_setup(char *str)
29{
30 alloc_bootmem_cpumask_var(&irq_default_affinity);
31 cpulist_parse(str, irq_default_affinity);
32 /*
33 * Set at least the boot cpu. We don't want to end up with
34 * bugreports caused by random comandline masks
35 */
36 cpumask_set_cpu(smp_processor_id(), irq_default_affinity);
37 return 1;
38}
39__setup("irqaffinity=", irq_affinity_setup);
40
41static void __init init_irq_default_affinity(void)
42{
43 if (!cpumask_available(irq_default_affinity))
44 zalloc_cpumask_var(&irq_default_affinity, GFP_NOWAIT);
45 if (cpumask_empty(irq_default_affinity))
46 cpumask_setall(irq_default_affinity);
47}
48#else
49static void __init init_irq_default_affinity(void)
50{
51}
52#endif
53
54#ifdef CONFIG_SMP
55static int alloc_masks(struct irq_desc *desc, int node)
56{
57 if (!zalloc_cpumask_var_node(&desc->irq_common_data.affinity,
58 GFP_KERNEL, node))
59 return -ENOMEM;
60
61#ifdef CONFIG_GENERIC_IRQ_EFFECTIVE_AFF_MASK
62 if (!zalloc_cpumask_var_node(&desc->irq_common_data.effective_affinity,
63 GFP_KERNEL, node)) {
64 free_cpumask_var(desc->irq_common_data.affinity);
65 return -ENOMEM;
66 }
67#endif
68
69#ifdef CONFIG_GENERIC_PENDING_IRQ
70 if (!zalloc_cpumask_var_node(&desc->pending_mask, GFP_KERNEL, node)) {
71#ifdef CONFIG_GENERIC_IRQ_EFFECTIVE_AFF_MASK
72 free_cpumask_var(desc->irq_common_data.effective_affinity);
73#endif
74 free_cpumask_var(desc->irq_common_data.affinity);
75 return -ENOMEM;
76 }
77#endif
78 return 0;
79}
80
81static void desc_smp_init(struct irq_desc *desc, int node,
82 const struct cpumask *affinity)
83{
84 if (!affinity)
85 affinity = irq_default_affinity;
86 cpumask_copy(desc->irq_common_data.affinity, affinity);
87
88#ifdef CONFIG_GENERIC_PENDING_IRQ
89 cpumask_clear(desc->pending_mask);
90#endif
91#ifdef CONFIG_NUMA
92 desc->irq_common_data.node = node;
93#endif
94}
95
96#else
97static inline int
98alloc_masks(struct irq_desc *desc, int node) { return 0; }
99static inline void
100desc_smp_init(struct irq_desc *desc, int node, const struct cpumask *affinity) { }
101#endif
102
103static void desc_set_defaults(unsigned int irq, struct irq_desc *desc, int node,
104 const struct cpumask *affinity, struct module *owner)
105{
106 int cpu;
107
108 desc->irq_common_data.handler_data = NULL;
109 desc->irq_common_data.msi_desc = NULL;
110
111 desc->irq_data.common = &desc->irq_common_data;
112 desc->irq_data.irq = irq;
113 desc->irq_data.chip = &no_irq_chip;
114 desc->irq_data.chip_data = NULL;
115 irq_settings_clr_and_set(desc, ~0, _IRQ_DEFAULT_INIT_FLAGS);
116 irqd_set(&desc->irq_data, IRQD_IRQ_DISABLED);
117 irqd_set(&desc->irq_data, IRQD_IRQ_MASKED);
118 desc->handle_irq = handle_bad_irq;
119 desc->depth = 1;
120 desc->irq_count = 0;
121 desc->irqs_unhandled = 0;
122 desc->tot_count = 0;
123 desc->name = NULL;
124 desc->owner = owner;
125 for_each_possible_cpu(cpu)
126 *per_cpu_ptr(desc->kstat_irqs, cpu) = 0;
127 desc_smp_init(desc, node, affinity);
128}
129
130int nr_irqs = NR_IRQS;
131EXPORT_SYMBOL_GPL(nr_irqs);
132
133static DEFINE_MUTEX(sparse_irq_lock);
134static DECLARE_BITMAP(allocated_irqs, IRQ_BITMAP_BITS);
135
136#ifdef CONFIG_SPARSE_IRQ
137
138static void irq_kobj_release(struct kobject *kobj);
139
140#ifdef CONFIG_SYSFS
141static struct kobject *irq_kobj_base;
142
143#define IRQ_ATTR_RO(_name) \
144static struct kobj_attribute _name##_attr = __ATTR_RO(_name)
145
146static ssize_t per_cpu_count_show(struct kobject *kobj,
147 struct kobj_attribute *attr, char *buf)
148{
149 struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
150 int cpu, irq = desc->irq_data.irq;
151 ssize_t ret = 0;
152 char *p = "";
153
154 for_each_possible_cpu(cpu) {
155 unsigned int c = kstat_irqs_cpu(irq, cpu);
156
157 ret += scnprintf(buf + ret, PAGE_SIZE - ret, "%s%u", p, c);
158 p = ",";
159 }
160
161 ret += scnprintf(buf + ret, PAGE_SIZE - ret, "\n");
162 return ret;
163}
164IRQ_ATTR_RO(per_cpu_count);
165
166static ssize_t chip_name_show(struct kobject *kobj,
167 struct kobj_attribute *attr, char *buf)
168{
169 struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
170 ssize_t ret = 0;
171
172 raw_spin_lock_irq(&desc->lock);
173 if (desc->irq_data.chip && desc->irq_data.chip->name) {
174 ret = scnprintf(buf, PAGE_SIZE, "%s\n",
175 desc->irq_data.chip->name);
176 }
177 raw_spin_unlock_irq(&desc->lock);
178
179 return ret;
180}
181IRQ_ATTR_RO(chip_name);
182
183static ssize_t hwirq_show(struct kobject *kobj,
184 struct kobj_attribute *attr, char *buf)
185{
186 struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
187 ssize_t ret = 0;
188
189 raw_spin_lock_irq(&desc->lock);
190 if (desc->irq_data.domain)
191 ret = sprintf(buf, "%d\n", (int)desc->irq_data.hwirq);
192 raw_spin_unlock_irq(&desc->lock);
193
194 return ret;
195}
196IRQ_ATTR_RO(hwirq);
197
198static ssize_t type_show(struct kobject *kobj,
199 struct kobj_attribute *attr, char *buf)
200{
201 struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
202 ssize_t ret = 0;
203
204 raw_spin_lock_irq(&desc->lock);
205 ret = sprintf(buf, "%s\n",
206 irqd_is_level_type(&desc->irq_data) ? "level" : "edge");
207 raw_spin_unlock_irq(&desc->lock);
208
209 return ret;
210
211}
212IRQ_ATTR_RO(type);
213
214static ssize_t wakeup_show(struct kobject *kobj,
215 struct kobj_attribute *attr, char *buf)
216{
217 struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
218 ssize_t ret = 0;
219
220 raw_spin_lock_irq(&desc->lock);
221 ret = sprintf(buf, "%s\n",
222 irqd_is_wakeup_set(&desc->irq_data) ? "enabled" : "disabled");
223 raw_spin_unlock_irq(&desc->lock);
224
225 return ret;
226
227}
228IRQ_ATTR_RO(wakeup);
229
230static ssize_t name_show(struct kobject *kobj,
231 struct kobj_attribute *attr, char *buf)
232{
233 struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
234 ssize_t ret = 0;
235
236 raw_spin_lock_irq(&desc->lock);
237 if (desc->name)
238 ret = scnprintf(buf, PAGE_SIZE, "%s\n", desc->name);
239 raw_spin_unlock_irq(&desc->lock);
240
241 return ret;
242}
243IRQ_ATTR_RO(name);
244
245static ssize_t actions_show(struct kobject *kobj,
246 struct kobj_attribute *attr, char *buf)
247{
248 struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
249 struct irqaction *action;
250 ssize_t ret = 0;
251 char *p = "";
252
253 raw_spin_lock_irq(&desc->lock);
254 for (action = desc->action; action != NULL; action = action->next) {
255 ret += scnprintf(buf + ret, PAGE_SIZE - ret, "%s%s",
256 p, action->name);
257 p = ",";
258 }
259 raw_spin_unlock_irq(&desc->lock);
260
261 if (ret)
262 ret += scnprintf(buf + ret, PAGE_SIZE - ret, "\n");
263
264 return ret;
265}
266IRQ_ATTR_RO(actions);
267
268static struct attribute *irq_attrs[] = {
269 &per_cpu_count_attr.attr,
270 &chip_name_attr.attr,
271 &hwirq_attr.attr,
272 &type_attr.attr,
273 &wakeup_attr.attr,
274 &name_attr.attr,
275 &actions_attr.attr,
276 NULL
277};
278ATTRIBUTE_GROUPS(irq);
279
280static struct kobj_type irq_kobj_type = {
281 .release = irq_kobj_release,
282 .sysfs_ops = &kobj_sysfs_ops,
283 .default_groups = irq_groups,
284};
285
286static void irq_sysfs_add(int irq, struct irq_desc *desc)
287{
288 if (irq_kobj_base) {
289 /*
290 * Continue even in case of failure as this is nothing
291 * crucial.
292 */
293 if (kobject_add(&desc->kobj, irq_kobj_base, "%d", irq))
294 pr_warn("Failed to add kobject for irq %d\n", irq);
295 }
296}
297
298static void irq_sysfs_del(struct irq_desc *desc)
299{
300 /*
301 * If irq_sysfs_init() has not yet been invoked (early boot), then
302 * irq_kobj_base is NULL and the descriptor was never added.
303 * kobject_del() complains about a object with no parent, so make
304 * it conditional.
305 */
306 if (irq_kobj_base)
307 kobject_del(&desc->kobj);
308}
309
310static int __init irq_sysfs_init(void)
311{
312 struct irq_desc *desc;
313 int irq;
314
315 /* Prevent concurrent irq alloc/free */
316 irq_lock_sparse();
317
318 irq_kobj_base = kobject_create_and_add("irq", kernel_kobj);
319 if (!irq_kobj_base) {
320 irq_unlock_sparse();
321 return -ENOMEM;
322 }
323
324 /* Add the already allocated interrupts */
325 for_each_irq_desc(irq, desc)
326 irq_sysfs_add(irq, desc);
327 irq_unlock_sparse();
328
329 return 0;
330}
331postcore_initcall(irq_sysfs_init);
332
333#else /* !CONFIG_SYSFS */
334
335static struct kobj_type irq_kobj_type = {
336 .release = irq_kobj_release,
337};
338
339static void irq_sysfs_add(int irq, struct irq_desc *desc) {}
340static void irq_sysfs_del(struct irq_desc *desc) {}
341
342#endif /* CONFIG_SYSFS */
343
344static RADIX_TREE(irq_desc_tree, GFP_KERNEL);
345
346static void irq_insert_desc(unsigned int irq, struct irq_desc *desc)
347{
348 radix_tree_insert(&irq_desc_tree, irq, desc);
349}
350
351struct irq_desc *irq_to_desc(unsigned int irq)
352{
353 return radix_tree_lookup(&irq_desc_tree, irq);
354}
355EXPORT_SYMBOL(irq_to_desc);
356
357static void delete_irq_desc(unsigned int irq)
358{
359 radix_tree_delete(&irq_desc_tree, irq);
360}
361
362#ifdef CONFIG_SMP
363static void free_masks(struct irq_desc *desc)
364{
365#ifdef CONFIG_GENERIC_PENDING_IRQ
366 free_cpumask_var(desc->pending_mask);
367#endif
368 free_cpumask_var(desc->irq_common_data.affinity);
369#ifdef CONFIG_GENERIC_IRQ_EFFECTIVE_AFF_MASK
370 free_cpumask_var(desc->irq_common_data.effective_affinity);
371#endif
372}
373#else
374static inline void free_masks(struct irq_desc *desc) { }
375#endif
376
377void irq_lock_sparse(void)
378{
379 mutex_lock(&sparse_irq_lock);
380}
381
382void irq_unlock_sparse(void)
383{
384 mutex_unlock(&sparse_irq_lock);
385}
386
387static struct irq_desc *alloc_desc(int irq, int node, unsigned int flags,
388 const struct cpumask *affinity,
389 struct module *owner)
390{
391 struct irq_desc *desc;
392
393 desc = kzalloc_node(sizeof(*desc), GFP_KERNEL, node);
394 if (!desc)
395 return NULL;
396 /* allocate based on nr_cpu_ids */
397 desc->kstat_irqs = alloc_percpu(unsigned int);
398 if (!desc->kstat_irqs)
399 goto err_desc;
400
401 if (alloc_masks(desc, node))
402 goto err_kstat;
403
404 raw_spin_lock_init(&desc->lock);
405 lockdep_set_class(&desc->lock, &irq_desc_lock_class);
406 mutex_init(&desc->request_mutex);
407 init_rcu_head(&desc->rcu);
408
409 desc_set_defaults(irq, desc, node, affinity, owner);
410 irqd_set(&desc->irq_data, flags);
411 kobject_init(&desc->kobj, &irq_kobj_type);
412
413 return desc;
414
415err_kstat:
416 free_percpu(desc->kstat_irqs);
417err_desc:
418 kfree(desc);
419 return NULL;
420}
421
422static void irq_kobj_release(struct kobject *kobj)
423{
424 struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
425
426 free_masks(desc);
427 free_percpu(desc->kstat_irqs);
428 kfree(desc);
429}
430
431static void delayed_free_desc(struct rcu_head *rhp)
432{
433 struct irq_desc *desc = container_of(rhp, struct irq_desc, rcu);
434
435 kobject_put(&desc->kobj);
436}
437
438static void free_desc(unsigned int irq)
439{
440 struct irq_desc *desc = irq_to_desc(irq);
441
442 irq_remove_debugfs_entry(desc);
443 unregister_irq_proc(irq, desc);
444
445 /*
446 * sparse_irq_lock protects also show_interrupts() and
447 * kstat_irq_usr(). Once we deleted the descriptor from the
448 * sparse tree we can free it. Access in proc will fail to
449 * lookup the descriptor.
450 *
451 * The sysfs entry must be serialized against a concurrent
452 * irq_sysfs_init() as well.
453 */
454 irq_sysfs_del(desc);
455 delete_irq_desc(irq);
456
457 /*
458 * We free the descriptor, masks and stat fields via RCU. That
459 * allows demultiplex interrupts to do rcu based management of
460 * the child interrupts.
461 * This also allows us to use rcu in kstat_irqs_usr().
462 */
463 call_rcu(&desc->rcu, delayed_free_desc);
464}
465
466static int alloc_descs(unsigned int start, unsigned int cnt, int node,
467 const struct irq_affinity_desc *affinity,
468 struct module *owner)
469{
470 struct irq_desc *desc;
471 int i;
472
473 /* Validate affinity mask(s) */
474 if (affinity) {
475 for (i = 0; i < cnt; i++) {
476 if (cpumask_empty(&affinity[i].mask))
477 return -EINVAL;
478 }
479 }
480
481 for (i = 0; i < cnt; i++) {
482 const struct cpumask *mask = NULL;
483 unsigned int flags = 0;
484
485 if (affinity) {
486 if (affinity->is_managed) {
487 flags = IRQD_AFFINITY_MANAGED |
488 IRQD_MANAGED_SHUTDOWN;
489 }
490 mask = &affinity->mask;
491 node = cpu_to_node(cpumask_first(mask));
492 affinity++;
493 }
494
495 desc = alloc_desc(start + i, node, flags, mask, owner);
496 if (!desc)
497 goto err;
498 irq_insert_desc(start + i, desc);
499 irq_sysfs_add(start + i, desc);
500 irq_add_debugfs_entry(start + i, desc);
501 }
502 bitmap_set(allocated_irqs, start, cnt);
503 return start;
504
505err:
506 for (i--; i >= 0; i--)
507 free_desc(start + i);
508 return -ENOMEM;
509}
510
511static int irq_expand_nr_irqs(unsigned int nr)
512{
513 if (nr > IRQ_BITMAP_BITS)
514 return -ENOMEM;
515 nr_irqs = nr;
516 return 0;
517}
518
519int __init early_irq_init(void)
520{
521 int i, initcnt, node = first_online_node;
522 struct irq_desc *desc;
523
524 init_irq_default_affinity();
525
526 /* Let arch update nr_irqs and return the nr of preallocated irqs */
527 initcnt = arch_probe_nr_irqs();
528 printk(KERN_INFO "NR_IRQS: %d, nr_irqs: %d, preallocated irqs: %d\n",
529 NR_IRQS, nr_irqs, initcnt);
530
531 if (WARN_ON(nr_irqs > IRQ_BITMAP_BITS))
532 nr_irqs = IRQ_BITMAP_BITS;
533
534 if (WARN_ON(initcnt > IRQ_BITMAP_BITS))
535 initcnt = IRQ_BITMAP_BITS;
536
537 if (initcnt > nr_irqs)
538 nr_irqs = initcnt;
539
540 for (i = 0; i < initcnt; i++) {
541 desc = alloc_desc(i, node, 0, NULL, NULL);
542 set_bit(i, allocated_irqs);
543 irq_insert_desc(i, desc);
544 }
545 return arch_early_irq_init();
546}
547
548#else /* !CONFIG_SPARSE_IRQ */
549
550struct irq_desc irq_desc[NR_IRQS] __cacheline_aligned_in_smp = {
551 [0 ... NR_IRQS-1] = {
552 .handle_irq = handle_bad_irq,
553 .depth = 1,
554 .lock = __RAW_SPIN_LOCK_UNLOCKED(irq_desc->lock),
555 }
556};
557
558int __init early_irq_init(void)
559{
560 int count, i, node = first_online_node;
561 struct irq_desc *desc;
562
563 init_irq_default_affinity();
564
565 printk(KERN_INFO "NR_IRQS: %d\n", NR_IRQS);
566
567 desc = irq_desc;
568 count = ARRAY_SIZE(irq_desc);
569
570 for (i = 0; i < count; i++) {
571 desc[i].kstat_irqs = alloc_percpu(unsigned int);
572 alloc_masks(&desc[i], node);
573 raw_spin_lock_init(&desc[i].lock);
574 lockdep_set_class(&desc[i].lock, &irq_desc_lock_class);
575 mutex_init(&desc[i].request_mutex);
576 desc_set_defaults(i, &desc[i], node, NULL, NULL);
577 }
578 return arch_early_irq_init();
579}
580
581struct irq_desc *irq_to_desc(unsigned int irq)
582{
583 return (irq < NR_IRQS) ? irq_desc + irq : NULL;
584}
585EXPORT_SYMBOL(irq_to_desc);
586
587static void free_desc(unsigned int irq)
588{
589 struct irq_desc *desc = irq_to_desc(irq);
590 unsigned long flags;
591
592 raw_spin_lock_irqsave(&desc->lock, flags);
593 desc_set_defaults(irq, desc, irq_desc_get_node(desc), NULL, NULL);
594 raw_spin_unlock_irqrestore(&desc->lock, flags);
595}
596
597static inline int alloc_descs(unsigned int start, unsigned int cnt, int node,
598 const struct irq_affinity_desc *affinity,
599 struct module *owner)
600{
601 u32 i;
602
603 for (i = 0; i < cnt; i++) {
604 struct irq_desc *desc = irq_to_desc(start + i);
605
606 desc->owner = owner;
607 }
608 bitmap_set(allocated_irqs, start, cnt);
609 return start;
610}
611
612static int irq_expand_nr_irqs(unsigned int nr)
613{
614 return -ENOMEM;
615}
616
617void irq_mark_irq(unsigned int irq)
618{
619 mutex_lock(&sparse_irq_lock);
620 bitmap_set(allocated_irqs, irq, 1);
621 mutex_unlock(&sparse_irq_lock);
622}
623
624#ifdef CONFIG_GENERIC_IRQ_LEGACY
625void irq_init_desc(unsigned int irq)
626{
627 free_desc(irq);
628}
629#endif
630
631#endif /* !CONFIG_SPARSE_IRQ */
632
633/**
634 * generic_handle_irq - Invoke the handler for a particular irq
635 * @irq: The irq number to handle
636 *
637 */
638int generic_handle_irq(unsigned int irq)
639{
640 struct irq_desc *desc = irq_to_desc(irq);
641
642 if (!desc)
643 return -EINVAL;
644 generic_handle_irq_desc(desc);
645 return 0;
646}
647EXPORT_SYMBOL_GPL(generic_handle_irq);
648
649#ifdef CONFIG_HANDLE_DOMAIN_IRQ
650/**
651 * __handle_domain_irq - Invoke the handler for a HW irq belonging to a domain
652 * @domain: The domain where to perform the lookup
653 * @hwirq: The HW irq number to convert to a logical one
654 * @lookup: Whether to perform the domain lookup or not
655 * @regs: Register file coming from the low-level handling code
656 *
657 * Returns: 0 on success, or -EINVAL if conversion has failed
658 */
659int __handle_domain_irq(struct irq_domain *domain, unsigned int hwirq,
660 bool lookup, struct pt_regs *regs)
661{
662 struct pt_regs *old_regs = set_irq_regs(regs);
663 unsigned int irq = hwirq;
664 int ret = 0;
665
666 irq_enter();
667
668#ifdef CONFIG_IRQ_DOMAIN
669 if (lookup)
670 irq = irq_find_mapping(domain, hwirq);
671#endif
672
673 /*
674 * Some hardware gives randomly wrong interrupts. Rather
675 * than crashing, do something sensible.
676 */
677 if (unlikely(!irq || irq >= nr_irqs)) {
678 ack_bad_irq(irq);
679 ret = -EINVAL;
680 } else {
681 generic_handle_irq(irq);
682 }
683
684 irq_exit();
685 set_irq_regs(old_regs);
686 return ret;
687}
688
689#ifdef CONFIG_IRQ_DOMAIN
690/**
691 * handle_domain_nmi - Invoke the handler for a HW irq belonging to a domain
692 * @domain: The domain where to perform the lookup
693 * @hwirq: The HW irq number to convert to a logical one
694 * @regs: Register file coming from the low-level handling code
695 *
696 * This function must be called from an NMI context.
697 *
698 * Returns: 0 on success, or -EINVAL if conversion has failed
699 */
700int handle_domain_nmi(struct irq_domain *domain, unsigned int hwirq,
701 struct pt_regs *regs)
702{
703 struct pt_regs *old_regs = set_irq_regs(regs);
704 unsigned int irq;
705 int ret = 0;
706
707 /*
708 * NMI context needs to be setup earlier in order to deal with tracing.
709 */
710 WARN_ON(!in_nmi());
711
712 irq = irq_find_mapping(domain, hwirq);
713
714 /*
715 * ack_bad_irq is not NMI-safe, just report
716 * an invalid interrupt.
717 */
718 if (likely(irq))
719 generic_handle_irq(irq);
720 else
721 ret = -EINVAL;
722
723 set_irq_regs(old_regs);
724 return ret;
725}
726#endif
727#endif
728
729/* Dynamic interrupt handling */
730
731/**
732 * irq_free_descs - free irq descriptors
733 * @from: Start of descriptor range
734 * @cnt: Number of consecutive irqs to free
735 */
736void irq_free_descs(unsigned int from, unsigned int cnt)
737{
738 int i;
739
740 if (from >= nr_irqs || (from + cnt) > nr_irqs)
741 return;
742
743 mutex_lock(&sparse_irq_lock);
744 for (i = 0; i < cnt; i++)
745 free_desc(from + i);
746
747 bitmap_clear(allocated_irqs, from, cnt);
748 mutex_unlock(&sparse_irq_lock);
749}
750EXPORT_SYMBOL_GPL(irq_free_descs);
751
752/**
753 * irq_alloc_descs - allocate and initialize a range of irq descriptors
754 * @irq: Allocate for specific irq number if irq >= 0
755 * @from: Start the search from this irq number
756 * @cnt: Number of consecutive irqs to allocate.
757 * @node: Preferred node on which the irq descriptor should be allocated
758 * @owner: Owning module (can be NULL)
759 * @affinity: Optional pointer to an affinity mask array of size @cnt which
760 * hints where the irq descriptors should be allocated and which
761 * default affinities to use
762 *
763 * Returns the first irq number or error code
764 */
765int __ref
766__irq_alloc_descs(int irq, unsigned int from, unsigned int cnt, int node,
767 struct module *owner, const struct irq_affinity_desc *affinity)
768{
769 int start, ret;
770
771 if (!cnt)
772 return -EINVAL;
773
774 if (irq >= 0) {
775 if (from > irq)
776 return -EINVAL;
777 from = irq;
778 } else {
779 /*
780 * For interrupts which are freely allocated the
781 * architecture can force a lower bound to the @from
782 * argument. x86 uses this to exclude the GSI space.
783 */
784 from = arch_dynirq_lower_bound(from);
785 }
786
787 mutex_lock(&sparse_irq_lock);
788
789 start = bitmap_find_next_zero_area(allocated_irqs, IRQ_BITMAP_BITS,
790 from, cnt, 0);
791 ret = -EEXIST;
792 if (irq >=0 && start != irq)
793 goto unlock;
794
795 if (start + cnt > nr_irqs) {
796 ret = irq_expand_nr_irqs(start + cnt);
797 if (ret)
798 goto unlock;
799 }
800 ret = alloc_descs(start, cnt, node, affinity, owner);
801unlock:
802 mutex_unlock(&sparse_irq_lock);
803 return ret;
804}
805EXPORT_SYMBOL_GPL(__irq_alloc_descs);
806
807#ifdef CONFIG_GENERIC_IRQ_LEGACY_ALLOC_HWIRQ
808/**
809 * irq_alloc_hwirqs - Allocate an irq descriptor and initialize the hardware
810 * @cnt: number of interrupts to allocate
811 * @node: node on which to allocate
812 *
813 * Returns an interrupt number > 0 or 0, if the allocation fails.
814 */
815unsigned int irq_alloc_hwirqs(int cnt, int node)
816{
817 int i, irq = __irq_alloc_descs(-1, 0, cnt, node, NULL, NULL);
818
819 if (irq < 0)
820 return 0;
821
822 for (i = irq; cnt > 0; i++, cnt--) {
823 if (arch_setup_hwirq(i, node))
824 goto err;
825 irq_clear_status_flags(i, _IRQ_NOREQUEST);
826 }
827 return irq;
828
829err:
830 for (i--; i >= irq; i--) {
831 irq_set_status_flags(i, _IRQ_NOREQUEST | _IRQ_NOPROBE);
832 arch_teardown_hwirq(i);
833 }
834 irq_free_descs(irq, cnt);
835 return 0;
836}
837EXPORT_SYMBOL_GPL(irq_alloc_hwirqs);
838
839/**
840 * irq_free_hwirqs - Free irq descriptor and cleanup the hardware
841 * @from: Free from irq number
842 * @cnt: number of interrupts to free
843 *
844 */
845void irq_free_hwirqs(unsigned int from, int cnt)
846{
847 int i, j;
848
849 for (i = from, j = cnt; j > 0; i++, j--) {
850 irq_set_status_flags(i, _IRQ_NOREQUEST | _IRQ_NOPROBE);
851 arch_teardown_hwirq(i);
852 }
853 irq_free_descs(from, cnt);
854}
855EXPORT_SYMBOL_GPL(irq_free_hwirqs);
856#endif
857
858/**
859 * irq_get_next_irq - get next allocated irq number
860 * @offset: where to start the search
861 *
862 * Returns next irq number after offset or nr_irqs if none is found.
863 */
864unsigned int irq_get_next_irq(unsigned int offset)
865{
866 return find_next_bit(allocated_irqs, nr_irqs, offset);
867}
868
869struct irq_desc *
870__irq_get_desc_lock(unsigned int irq, unsigned long *flags, bool bus,
871 unsigned int check)
872{
873 struct irq_desc *desc = irq_to_desc(irq);
874
875 if (desc) {
876 if (check & _IRQ_DESC_CHECK) {
877 if ((check & _IRQ_DESC_PERCPU) &&
878 !irq_settings_is_per_cpu_devid(desc))
879 return NULL;
880
881 if (!(check & _IRQ_DESC_PERCPU) &&
882 irq_settings_is_per_cpu_devid(desc))
883 return NULL;
884 }
885
886 if (bus)
887 chip_bus_lock(desc);
888 raw_spin_lock_irqsave(&desc->lock, *flags);
889 }
890 return desc;
891}
892
893void __irq_put_desc_unlock(struct irq_desc *desc, unsigned long flags, bool bus)
894{
895 raw_spin_unlock_irqrestore(&desc->lock, flags);
896 if (bus)
897 chip_bus_sync_unlock(desc);
898}
899
900int irq_set_percpu_devid_partition(unsigned int irq,
901 const struct cpumask *affinity)
902{
903 struct irq_desc *desc = irq_to_desc(irq);
904
905 if (!desc)
906 return -EINVAL;
907
908 if (desc->percpu_enabled)
909 return -EINVAL;
910
911 desc->percpu_enabled = kzalloc(sizeof(*desc->percpu_enabled), GFP_KERNEL);
912
913 if (!desc->percpu_enabled)
914 return -ENOMEM;
915
916 if (affinity)
917 desc->percpu_affinity = affinity;
918 else
919 desc->percpu_affinity = cpu_possible_mask;
920
921 irq_set_percpu_devid_flags(irq);
922 return 0;
923}
924
925int irq_set_percpu_devid(unsigned int irq)
926{
927 return irq_set_percpu_devid_partition(irq, NULL);
928}
929
930int irq_get_percpu_devid_partition(unsigned int irq, struct cpumask *affinity)
931{
932 struct irq_desc *desc = irq_to_desc(irq);
933
934 if (!desc || !desc->percpu_enabled)
935 return -EINVAL;
936
937 if (affinity)
938 cpumask_copy(affinity, desc->percpu_affinity);
939
940 return 0;
941}
942EXPORT_SYMBOL_GPL(irq_get_percpu_devid_partition);
943
944void kstat_incr_irq_this_cpu(unsigned int irq)
945{
946 kstat_incr_irqs_this_cpu(irq_to_desc(irq));
947}
948
949/**
950 * kstat_irqs_cpu - Get the statistics for an interrupt on a cpu
951 * @irq: The interrupt number
952 * @cpu: The cpu number
953 *
954 * Returns the sum of interrupt counts on @cpu since boot for
955 * @irq. The caller must ensure that the interrupt is not removed
956 * concurrently.
957 */
958unsigned int kstat_irqs_cpu(unsigned int irq, int cpu)
959{
960 struct irq_desc *desc = irq_to_desc(irq);
961
962 return desc && desc->kstat_irqs ?
963 *per_cpu_ptr(desc->kstat_irqs, cpu) : 0;
964}
965
966static bool irq_is_nmi(struct irq_desc *desc)
967{
968 return desc->istate & IRQS_NMI;
969}
970
971/**
972 * kstat_irqs - Get the statistics for an interrupt
973 * @irq: The interrupt number
974 *
975 * Returns the sum of interrupt counts on all cpus since boot for
976 * @irq. The caller must ensure that the interrupt is not removed
977 * concurrently.
978 */
979unsigned int kstat_irqs(unsigned int irq)
980{
981 struct irq_desc *desc = irq_to_desc(irq);
982 unsigned int sum = 0;
983 int cpu;
984
985 if (!desc || !desc->kstat_irqs)
986 return 0;
987 if (!irq_settings_is_per_cpu_devid(desc) &&
988 !irq_settings_is_per_cpu(desc) &&
989 !irq_is_nmi(desc))
990 return desc->tot_count;
991
992 for_each_possible_cpu(cpu)
993 sum += *per_cpu_ptr(desc->kstat_irqs, cpu);
994 return sum;
995}
996
997/**
998 * kstat_irqs_usr - Get the statistics for an interrupt
999 * @irq: The interrupt number
1000 *
1001 * Returns the sum of interrupt counts on all cpus since boot for @irq.
1002 * Contrary to kstat_irqs() this can be called from any context.
1003 * It uses rcu since a concurrent removal of an interrupt descriptor is
1004 * observing an rcu grace period before delayed_free_desc()/irq_kobj_release().
1005 */
1006unsigned int kstat_irqs_usr(unsigned int irq)
1007{
1008 unsigned int sum;
1009
1010 rcu_read_lock();
1011 sum = kstat_irqs(irq);
1012 rcu_read_unlock();
1013 return sum;
1014}